Alaska automobile registration and territory-issued plates began in 1921.  With only five plates known, the 1921 Alaska is among the rarest in the United States.  The traditional Alaskan flag graphic began in 1948.  Alaska became the 49th state on January 3, 1959, after 1959 tabs had already been issued for the 1958 base plates, so 1960 is considered to be the first state-issued plate.  The earliest of the five currently valid base plates began issue in 1981.